Human existence along the river goes back to the beginning of life on earth; several tumuli in the region provide evidence about human settlement dating from prehistoric times.  In this part of the country, the landscape shaped by the Tigris River provides a spectacular setting for settlement.  Cave dwellings, Roman ruins and Medieval monuments make up the impressive cultural heritage of this unique spot which is legally protected as an archaeological site of the First Degree.

 The Tigris River is one of the rivers mentioned in the Bible; a sacred natural element in the Biblical context-- It has given and continues to give life to the region. A significant cultural landscape has developed as a result of the strategic importance of the site and the suitable living conditions available at this important location.  The soft natural rock of the valleys around the Tigris   is easy to carve, offering the inhabitants the ability to shape their homes and religious buildings on the hillside; the proximity to fresh water sources has made it easy to continue living. Being on the Silk Road made the location favorable for commercial activity; Hasankeyf developed outside of the castle. Its caravansarays acted as a local market and a transfer point for goods coming from Asia and heading towards Europe.

With its interesting structures and ruins reflecting the basic features of a medieval Islamic town and its unmatched landscape, Hasankeyf is a jewel which requires utmost care for its protection.  Its authentic aura and beautiful scenery has great impact on its spectators.  Hasankeyf represents a universal value with its natural assets, historical landscape, featuring high quality in arts, architectural design and engineering.

To be included in the World Heritage List, Hasankeyf fullfills the following criteria:

I.  represent a masterpiece of human creative genius

The site of Hasankeyf has an outstanding value with its masterpieces such as the Zeynel Bey Tomb, Sultan Süleyman Mosque, the Bridge and the Castle overlooking the Tigris River.   Especially the gates of the Castle and the Bridge have superior designs and are unique examples of their types. Indeed, the bridge with its 40-metre span, exhibits an architectural excellence which rises above the masonry structures of the time.

II. exhibit an important interchange of human values, over a span of time or within a cultural area of the world, on developments in architecture or technology, monumental arts, town-planning or landscape design

Hasankeyf, which is located in northern Mesopotamia, is one of the world's ancient settlements. Life in the region was influenced by various powers, from the prehistoric times to Romans and Selcuks. One can see the high quality architectural works of the Artukid, Ayyubid and Akkoyunlu periods, which prove that several cultures contributed to the cultural fabric of Hasankeyf.  For instance, the architect of the Zeynel Bey Tomb, who came from Iran, introduced the use of glazed brick to a city which had a long and strong tradition in stone construction. The architectural form of the tomb is also new for the place; a style originated in Semerkand, the capital city of the Timurid Empire. Moving from Hasankeyf to the East or West one can find the use of the same style from Semerkand to Istanbul in the 15th century.  Skilled artists and artisans are known to be travelling from the East towards Anatolia during this period. Understanding and analyzing these relations is of great significance in terms of recognizing lost cultural links.
 
The bridge of Hasankeyf was famous with its 40-metre span. Its ruins are testimony to the fine details of the design. Though smaller in size, the large span bridge motif was revived in a bridge built in Mostar by architect Hayrettin  in  mid 16th century. Turks moved between the East and West, from Asia to Europe, and  were influenced  by all these lands and the cultures. Thus, Hasankeyf was home to many people (people of different origins) and enabled an accumulation of rich experiences through the centuries.  Hasankeyf inspired people who passed by this region; people who carried their experiences to far away lands and influenced other cultures. 

III bear a unique or at least exceptional testimony to a cultural tradition or to a civilisation which is living or which has disappeared

Hasankeyf is a unique city that preserved important traces from the Medieval  period. Its special location on the Tigris River and the urban remnants make it exceptional. 

Geographically, the region is influenced by Syrian and Persian architecture.  The fact that it was not subjected to total destruction by modern urbanisation makes the site even more significant. Recent excavations helped discover interesting architectural findings from Roman times and further back.

IV be an outstanding example of a type of building, architectural or technological ensemble or landscape which illustrates (a) significant stage(s) in human history

Hasankeyf hosts rare examples of Anatolian-Turkish Architecture. The building called   Kızlar Camii is an interesting example of funerary architecture.  Zeynel Bey Tomb with its cylindrical walls adorned with glazed tiles and topped by a double-shelled dome, is a special case: a unique example of Timurid Architecture  in Turkey.

Göreme in Cappadocia, also a World Heritage Site, is an interesting area with its rock-cut churches and underground cities.  In Hasankeyf also, many of the living spaces: houses, religious, commercial and other structures are carved into the rock, providing important historic and aesthetic data about life along the Tigris River over a long period of time. 

The choice of the position of the citadel contributed to the impact of the fortification. Citadels built over high cliffs can be found in many places.  However, the materials and the workmanship are not as elaborate as they are in Hasankeyf. The architectural quality of the gates and the kiosk called Small Palace are distinguished examples of military architecture in Anatolia.
  

V be an outstanding example of a traditional human settlement, land-use, or sea-use which is representative of a culture (or cultures), or human interaction with the environment especially when it has become vulnerable under the impact of irreversible change

Considering its special location and uniqueness, this historical settlement, which preserved its traditional living spaces cut into the rock, is an extraordinary conservation area with distinguished Medieval buildings. The water supply system, caves, stone houses, a bazaar carved into the rock on  an ascending  pathway  reflect  the arts and crafts, capabilities and cultural tradition of thousands of years. Living habits have changed in recent times and the settlers moved out from the caves in the twentieth century. At the moment, modern development is a great risk to the Medieval site.   Unfortunately, the surviving elements are very fragile; they are subject to weathering and pressures from tourism and dam construction.
 
VIIcontain superlative natural phenomena or areas of exceptional natural beauty and aesthetic importance

Hasankeyf is located to the north of the Tigris River that is one of the two major rivers forming Mesopotamia. The immediate clash between the dry lands of the Middle East and the abundant freshwater of the Tigris River resulted in exceptional natural beauty and extraordinary aesthetic segments of unique riparian ecosystems. The River is the main source of freshwater in these dry landscapes and everything else is shaped following the course of the river over the past several hundred thousand years. This includes human history that dates back for more than 10,000 years. The entire river course itself is an irreplaceable natural phenomenon, because it creates globally unique landscapes and riparian ecosystems while flowing from Turkey to the Gulf of Basra. These landscapes include deep canyons, humid gallery forests and sandbanks situated few hundreds of meters to semi-deserts and calcareous steppes that cover the wider landscape. The uniqueness of this natural phenomenon is further developed by the contribution of human that created monumental cultural landscapes embedded in the natural landscapes of the Tigris River. In Hasankeyf, one can hardly identify the boundaries between natural and cultural landscapes. This harmony makes Hasankeyf and the Tigris Valley not only globally unique, but also exceptionally beautiful and aesthetic.  

VIII be outstanding examples representing major stages of earth's history, including the record of life, significant on-going geological processes in the development of landforms, or significant geomorphic or physiographic features;

The Tigris River within the borders of Turkey is located in the south of the Arabian and Anatolian Plates' collision zone. As a result of the collision between these two geologically different plates, especially north of this zone uplifted; so the Tigris River formed its own river bed, especially around Hasankeyf and at the same time it migrated to the south. The Botan Creek Valley which reaches the Tigris River from Siirt will be, in major part, flooded if the Ilisu Dam is constructed. This valley is like the Grand Canyon of Turkey formed through extreme tectonic uplifts. As a result of the unique narrow topography of the valley, the planned dam will cover a very long part of the valley (136 km.) with a very small volume.

IX be outstanding examples representing significant on-going ecological and biological processes in the evolution and development of terrestrial, fresh water, coastal and marine ecosystems and communities of plants and animals

The Tigris River Valley represents the single remaining example of the riverine and canyon ecosystems in South-eastern Turkey after the depletion of similar ecosystems along the Firat (Euphrates) River. The area's uniqueness and irreplaceability is largely reflected in rare, vulnerable, migratory and endangered bird species and other biodiversity confined to the river valley (Welch 2004; Eken et al. 2006). Hence, Eken et al. (2006) describe five Key Biodiversity Areas (KBAs) (sites of global importance for conservation of biodiversity) along the Tigris River in Turkey. In addition to KBAs, Welch (2004) describes five Priority Areas forming a single integral ecosystem along the Dicle Valley, which consists of natural sites of outstanding importance for birds, as well as for other biodiversity and on-going ecological processes.

This stretch of river has been divided into five KBAs of different character and conservation priorities, but all function together as a whole and could thus justifiably be treated as one protected area for strategic conservation and river basin management. The entire freshwater community is unique to Mesopotamia and even to the segments of the Tigris River within Turkey, reflected by several endemic plant, fish and reptile species . The Tigris in Turkey is, as yet, an unaltered stretch of river and, despite dams further down and upstream, it still has a full complement of riverine habitats and, seasonal variations in water levels and flows. Therefore, the river is globally important for the continuation of ecological and biological processes in the evolution and development of fresh water ecosystems and species communities in this part of the world, i.e. in Mesopotamia.
X contain the most important and significant natural habitats for in-situ conservation of biological diversity, including those containing threatened species of outstanding universal value from the point of view of science or conservation.

The Tigris River has an outstanding importance for biodiversity in the world. It is the only natural river and canyon system remaining in Turkey. Especially after the destruction of natural sites along the Euphrates River (the other large river system in eastern Turkey) due to the construction of big dams, the importance of the Tigris has increased even more, as the only large river system in the region still relatively untouched and with good, viable, unique and rich habitats and biodiversity. The importance of this river system for the natural habitats and threatened species is very significant, as can be attested by the existence  of 5 Key Biodiversity Areas (KBAs) along its boundries of international importance for the conservation of nature1: the Bismil Plain, Tigris Valley, Küpeli Mountain, Eruh Mountains, Cizre and Silopi KBA

Among the five KBAs, the Tigris Valley hosts a unique area: Hasankeyf The Tigris Valley KBA holds a mosaic of different riverine ecosystems, from flood plains, stony and vegetated islands, and cliffs formed by seasonal fluctuations in the level and the flow rate of the river. Stony and sandy plains are present in the flood plain. Surrounding the river, mountains and flat steppes are frequent. In the mountainous parts, rare and unique oak forests can be found.

Species

Including influences from the Mediterranean, steppe and desert biomes, the Tigris Valley KBA hosts a huge diversity of biodiversity, including many endemic species like Cicer echinospermum, highly endangered and a priority target for conservation.

Located in the middle part of the Tigris Valley, Hasankeyf itself is a very important location for breeding of raptor species. Important populations of amazing raptors such as Bonelli's Eagle (Hieraaetus fasciatus),  lesser kestrel (Falco naumanni) (globally endangered), Egyptian vulture (Neophron percnopterus) (also globally endangered), and Eurasian Griffon (Gyps fulvus) adopt the cliffs of this magical place as their nesting zone. Steep and arid sandy hillsides are used as important breeding sites for rare bird species such as the little swift (Apus affinis), cinereous bunting (Emberiza cineracea) and pied kingfisher (Ceryle rudis).

The Euphrates soft-shell turtle (Rafetus euphraticus) is endemic to the Tigris and Euphrates river systems. In the Tigris River, it breeds on the sand dunes near the river shores.

The Bezoar goat (Capra aegagrus) uses the rock cliffs and the steep canyons in the Tigris valley. Together with the Striped hyaena (Hyaena hyaena), which lives in the caves and cavities at the site, it is among the priority mammal species in the KBA.

REFERENCES

Eken, G., Bozdoğan, M., İsfendiyaroğlu, S., Kılıç, D.T., Lise, Y. (editors) 2006. Türkiye'nin Önemli Doğa Alanları. Doğa Derneği, Ankara.
1  KBAs are areas of international importance for biodiversity and are selected by using standard, globally applicable and threshold-based criteria taking into account the distribution and population of species for which site conservation is appropriate. These criteria are built on two main principles of selection of sites conservation: vulnerability and irreplaceability. KBAs selected under the vulnerability principle host significant populations of threatened species whereas the irreplaceability principle is used for determining sites important for restricted range, congregatory and biome restricted species (Eken et al. 2006).